The above identified parent applications, and other disclosures such as U.S. Pat. No. 3,892,958 to C. Tung of July 1, 1975 relate to the programmable multi-purpose computer art. U.S. Pat. No. 3,967,273 to K. Knowlton of June 29, 1976; British Specification No. 1417849 filed Dec. 20, 1972; and European Patent Application 11,307 filed Nov. 19, 1979 relate to the multiple use of keyboard keys for reducing the number of keys required on a keyboard for typewriters and telephones. The parent applications relate to keyboard configurations particularly desirable in miniaturized multi-purpose computer systems now feasible in the art which are capable of many hundreds of functions and which require both numerics and alphabets in their communication, calculating and data processing operations.
The Knowlton patent, for example, represents the state of related prior art keyboards which reduce the number of keys required for alphanumeric capabilities in a telephone system by requiring two successive key stroke choices for every entry digit such as numeral 2 or letter k. However, many more keys are required in multiple purpose computers as seen by the Tung patent which provides for most keys to have three functions, wherein two sets of functions are respectively chosen by respective orange or blue prefix keys so that a calculator with thirty-two keys can be used for about three times that many functional computer entries including instructions and data. This latter concept is used, for example, in "Hewlett-Packard" Model HO-41 type programmable calculators with full alphabetic capabilities. Similarly "Texas Instruments" TI-88 line of programmable calculators have alphabetic capabilities with two keyboard functions selectable, plus an alphabetic entry mode.
The general state of the art of calculator systems with complex many functional capacity is represented by U.S. Pat. No. 3,863,060 to F. Rode et al. of Jan. 28, 1975.
However, the state of such prior art calculators has made programming and particularly programming in the alpha mode awkward and time consuming because of the necessity to use many key strokes in entry of complex instructions such as associated with writing programs. In particular the sequence of key stroke entries required for entering alphabet letters into program steps being formulated are burdensome in time taken and are so complex that a programmer must of necessity refer to complex sequences set out in instruction manuals, which may not even be accessible with the computer keyboard, particularly in the case of portable computers.
Also, many of these prior art calculators have introduced alpha capabilities at the expense of utilizing 26 separate keys for the alphabet. Thus, calculators or computers with few key keyboards in the art have been deficient in their capacity to control many calculator functions with concurrent alphanumeric capability that can be easily used and rapidly programmed in the alphanumeric mode.
It is therefore an objective of this invention to provide improved alphanumeric capabilities in computers and data processing system with simplified keyboards and instructions, and in particular to overcome the aforesaid deficiencies of the prior art. Other objects, features and advantages will be found throughout the following description, drawing and claims.